Stainless Steel Coil Tube — Product Technical Specification
1. Product Overview
The Stainless Steel Coil Tube (Product Reference No. 1654) manufactured by Wenzhou Jixing Metal Materials Co., Ltd is a precision-engineered tubular product supplied in continuous coil form, designed for high-performance applications across multiple industrial sectors. This product represents a modern advancement in tubular metal forming technology, incorporating design improvements derived from research on loom warp beam brackets and warp beam coil tube optimization (《织机经轴托脚及经轴盘管的改进》). The coil tube is engineered to deliver superior mechanical integrity, corrosion resistance, and dimensional consistency while maintaining the flexibility and ease of downstream processing inherent to coiled configurations.
Unlike discrete-length seamless or welded pipes, the coil tube format offers significant advantages in material utilization, logistics efficiency, and automation compatibility. The product is available in a range of diameters, wall thicknesses, and grades to meet the diverse requirements of manufacturing, energy, chemical processing, and textile machinery industries.
2. Material & Properties
The stainless steel coil tube is fabricated from austenitic and duplex stainless steel grades, selected to provide an optimal balance of mechanical strength, corrosion resistance, and formability. The following material grades are typically offered:
- SAE 304 / AISI 304 — General-purpose austenitic stainless steel with excellent corrosion resistance and weldability.
- SAE 316 / AISI 316 — Molybdenum-enhanced austenitic grade offering superior resistance to pitting and crevice corrosion.
- SAE 321 / AISI 321 — Stabilized austenitic grade suitable for elevated-temperature service.
- SAE 316L / AISI 316L — Low-carbon variant of 316 for enhanced weldability and intergranular corrosion resistance.
- SAE 304L / AISI 304L — Low-carbon variant of 304 for critical welding applications.
Key Mechanical Properties (Typical Values for SAE 304)
- Tensile Strength (UTS): ≥ 515 MPa (74,700 psi)
- Yield Strength (0.2% Offset): ≥ 205 MPa (29,700 psi)
- Elongation: ≥ 40%
- Hardness (Brinell): ≤ 201 HB
- Density: 8.0 g/cm³
- Thermal Conductivity: 16.3 W/(m·K) at 100°C
- Modulus of Elasticity: 193 GPa
Key Chemical Composition (Typical — SAE 304)
| Element | C | Si | Mn | P | S | Cr | Ni | N |
|---|---|---|---|---|---|---|---|---|
| Maximum (%) | 0.08 | 1.00 | 2.00 | 0.045 | 0.030 | 18.0–20.0 | 8.0–10.5 | — |
3. Specifications
The following table presents the standard dimensional and technical specifications for the Stainless Steel Coil Tube (Ref. No. 1654):
| Parameter | Specification | Standard / Reference |
|---|---|---|
| Product Name | Stainless Steel Coil Tube (盘管 Coiltube) | — |
| Product Reference No. | 1654 | Internal Catalog |
| Outer Diameter (OD) | 6.0 mm – 108.0 mm | ASTM A554 / ASME SA-554 |
| Wall Thickness | 0.5 mm – 6.0 mm | ASTM A554 / ASME SA-554 |
| OD Tolerance | ±0.10 mm (for OD ≤ 25 mm); ±0.15% (for OD > 25 mm) | ASTM A554 |
| Wall Thickness Tolerance | ±10% (minimum ±0.05 mm) | ASTM A554 |
| Surface Finish | No. 1 Annealed Pickled, 2B, BA (Bright Annealed), No. 4 Brushed | ASTM A480 |
| Coil ID (Inner Diameter of Coil) | 500 mm, 610 mm, or custom | Customer Specification |
| Coil Length | 500 m – 2000 m per coil (continuous) | — |
| Coil Weight | Up to 5,000 kg per coil | — |
| End Condition | Plain cut, deburred, or capped | — |
| Heat Treatment | Solution Annealed (1010°C – 1150°C), water quenched | ASTM A554 |
| Applicable Standards | ASTM A554, ASME SA-554, EN 10216-5, JIS G3446, GB/T 12771 | — |
4. Manufacturing Process
The production of the Stainless Steel Coil Tube follows a rigorous multi-stage manufacturing workflow designed to ensure dimensional precision, metallurgical homogeneity, and surface integrity:
- Hot Rolling / Slab Preparation: Continuous casting slabs of the selected stainless steel grade are reheated to the appropriate hot-rolling temperature (typically 1150°C – 1250°C) and rolled into flat strip or hollow tube blanks.
- Forming (ERW / Welded or Seamless):
- Welded Coil Tube: Flat strip is precision-cut, formed into a helical coil, and joined by Electro Resistance Welding (ERW) or High-Frequency Induction Welding (HFW). The weld seam is subsequently ground or polished to flush with the outer surface.
- Seamless Coil Tube: Hollow billets are pierced via hot or cold piercing and subsequently drawn or mandrel-rolled to the target dimensions.
- Solution Annealing: The formed tube is heated to 1010°C – 1150°C and rapidly quenched (water or controlled atmosphere) to achieve a fully austenitic microstructure, eliminate residual stresses, and restore corrosion resistance.
- Pickling and Passivation: The annealed tube is treated in a hydrofluoric/nitric acid bath to remove oxide scale, followed by passivation to establish a protective chromium oxide layer.
- Precision Sizing / Cold Drawing: For tight-tolerance applications, the tube undergoes cold drawing or rolling through calibrated dies to achieve final dimensional accuracy.
- Surface Finishing: Depending on the specified finish grade, the tube may undergo additional mechanical polishing, electropolishing, or chemical brightening.
- Coiling and Packaging: The finished tube is wound onto a core to form a coil of the specified inner diameter. Each coil is wrapped with moisture-barrier film, labeled with heat number and traceability data, and secured for transport.
5. Applications
The Stainless Steel Coil Tube (Ref. No. 1654) is widely deployed across multiple industrial domains. Notable applications include:
- Textile Machinery: The product has been specifically optimized for use in loom warp beam brackets and warp beam coil tube assemblies, where improved structural rigidity, reduced vibration, and enhanced fatigue resistance are critical for high-speed weaving operations.
- Automotive Industry: Exhaust system components, fuel lines, structural brackets, and heat exchanger tubes.
- Food and Pharmaceutical Processing: Hygienic fluid transfer lines, CIP (Clean-in-Place) systems, and process equipment where corrosion resistance and ease of cleaning are paramount.
- Chemical and Petrochemical Industry: Process piping, heat exchangers, reactor internals, and storage tank components exposed to aggressive chemical environments.
- Building and Construction: Architectural railings, decorative trim, structural supports, and HVAC (Heating, Ventilation, and Air Conditioning) ductwork.
- Medical Devices: Instrument tubing, endoscope guide wires, and surgical equipment components requiring biocompatibility and sterilizability.
- Energy Sector: Solar thermal collector tubes, heat exchanger coils, and nuclear-grade piping components.
6. Quality Certifications & Testing
Wenzhou Jixing Metal Materials Co., Ltd maintains a comprehensive quality management system and adheres to internationally recognized standards to ensure product conformity and traceability:
- ISO 9001:2015 — Quality Management System certification ensuring consistent production quality and continuous improvement.
- ISO 14001:2015 — Environmental Management System certification demonstrating commitment to sustainable manufacturing practices.
- ISO 45001:2018 — Occupational Health and Safety Management System certification.
- EN 10204 Type 3.1 Certificates — Third-party inspection certificates available for each heat/lot upon request.
- Mill Test Reports (MTR) — Comprehensive chemical analysis and mechanical property data provided with every shipment.
In-Process and Final Inspection Regimes
- Hydrostatic Testing: Each coil is pressure-tested at 1.5× the maximum design pressure to verify weld integrity and wall uniformity.
- Dimensional Inspection: Outer diameter, wall thickness, and roundness are measured at regular intervals using ultrasonic thickness gauges and optical comparators.
- Chemical Analysis: Spectrometric analysis (OES — Optical Emission Spectroscopy) of each heat to verify compositional conformance.
- Mechanical Testing: Tensile tests, hardness testing, and impact testing performed on representative samples from each production lot.
- Surface Defect Inspection: Visual and eddy current testing to detect surface discontinuities, cracks, or inclusions.
- Corrosion Testing: Salt spray testing (ASTM B117) and intergranular corrosion testing (ASTM A262) available for qualifying grades.
7. Unique Selling Points
- Optimized for Textile Machinery Applications: The design incorporates lessons learned from the improvement of loom warp beam brackets and warp beam coil tubes, resulting in enhanced fatigue performance, reduced operational vibration, and extended service life in high-cycle weaving environments.
- Continuous Coil Format: Eliminates butt-weld joints inherent to discrete pipe sections, reducing leak points, improving hydraulic integrity, and enabling fully automated downstream processing (cutting, bending, forming).
- Wide Dimensional Range: Available in ODs from 6.0 mm to 108.0 mm with wall thicknesses from 0.5 mm to 6.0 mm, covering a broad spectrum of engineering requirements from a single product family.
- Multi-Grade Availability: Selection from SAE 304, 316, 321, 304L, 316L and other grades ensures material suitability for diverse environmental and mechanical service conditions.
- Full Traceability: Each coil is heat-numbered and accompanied by complete mill test documentation, enabling full supply chain traceability from raw material to end product.
- Superior Surface Quality: Available in No. 1, 2B, BA, and No. 4 finishes, with electropolishing options for critical hygienic and aesthetic applications.
- Cost-Efficient Logistics: The coil format maximizes material utilization (reduced trim loss), minimizes packaging volume, and reduces transportation costs per unit length compared to discrete pipe sections.
8. Packaging & Delivery
- Each coil is wrapped in moisture-proof PE (Polyethylene) film and secured with steel strapping bands.
- Coils are packed on wooden pallets or in export-grade wooden crates with desiccant packs for international shipments.
- Markings on each coil include: Product Reference No., Grade, OD × WT (Wall Thickness), Heat Number, Coil Length, Net Weight, and Manufacturing Date.
- Custom packaging configurations are available upon request to meet customer-specific handling and storage requirements.
Note: All specifications are subject to revision without prior notice. For the most current product data, dimensional tolerances, and material certifications, customers are advised to contact Wenzhou Jixing Metal Materials Co., Ltd directly. Custom specifications and non-standard configurations are available through